Introduction This Core (A) of the Research Center will consist of the Director (the Principal Investigator of the entire Center), the Associate Director, Laurie Cutting, Ph.D., a Financial/Budget Administrator, a Program Administrator, and an Information Specialist. Through interlocking and overlapping relationships with the Mental Retardation Developmental Disabilities Research Center (MRDDRC), no statistical key personnel are represented directly within this Core;and the services of the expert statistics consultant, Dr. Scott Zeger, are financed as a function of MRDDRC. General Kennedy Krieger Institute support is provided for the Financial/Budget Administrator. Thus, there are major aspects of Core A that are available to Core A (as "central user" on behalf of this Research Center) that are services of the MRDDRC. How this has evolved will be described in the section on Organization.